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It has been tested and stamped in accordance with applicable
pressure codes for a maximum operating pressure of 2100
kPa refrigerant-side and 1000 kPa water-side.
The water connection of the heat exchanger is a Victaulic
connection. As an option the evaporator is available with
frost protection (evaporator frost protection option).
The products that may be added for thermal insulation of
the containers during the water piping connection procedure
must be chemically neutral in relation to the materials and
coatings to which they are applied. This is also the case for
the products originally supplied by Carrier.
10.2.2 - Oil separator
In these units, the oil separator is a pressure vessel that is
mounted under the outside vertical condenser coils. Dis-
charge gas at the compressor outlet is directed towards the
bottom of the oil separator ring and most of the oil separates
from the gas by strong deceleration and by gravity. The gas
then flows through a wire mesh screen where the remaining
oil is separated by coalescence and flows to the bottom of
the ring. The gas is now free from oil and leaves the ring at
the top towards the condenser.
The oil separator is equipped with a trace heater regulated
by the control. This heater is equipped with an internal
thermostat that disconnects the power supply when the
temperature reaches 85°C and automatically resets when
the temperature again falls to a normal value.
The products that may be added for thermal insulation of
the vessels during the water piping connection procedure
must be chemically neutral in relation to the materials and
coatings to which they are applied. This is also the case for
the products originally supplied by Carrier.
10.2.3 - economiser function
The economiser function includes a liquid line valve, a filter
drier, two EXVs, a plate heat exchanger as well as protection
devices (fuse or valve).
At the condenser outlet a part of the liquid is expanded
via the secondary EXV in one of the heat exchanger
circuits and then returns as gas at the compressor
economiser. This expansion permits increase of the liquid
sub-cooling of the rest of the flow that penetrates the
evaporator via the principal EXV. This permits increasing
the cooling capacity of the system as well as its efficiency.
10.3 - high-pressure safety switch
30XA units are equipped with high-pressure safety switches,
calibrated to 2200 kPa.
These pressure switches are located at the discharge of each
compressor.
10.4 - Condensers
The 30XA coils are micro-channel condensers made entirely
of aluminium. Optional coils with internally groved copper
tubes with aluminium fins are also available (options 254
and 255).
10.5 - fans
The fans are axial Flying Bird fans equipped with rotating
shroud and made of composite recyclable material. Each
motor is fixed with transverse supports. The motors are
three-phase, with permanently lubricated bearings and
insulation class F.
10.6 - Electronic expansion valve (EXV)
The EXV is equipped with a stepper motor (2785 to 3690
steps, depending on the model) that is controlled via the
EXV board.
The EXV is also equipped with a sightglass that permits
verification of the mechanism movement and the presence
of the liquid gasket.
10.7 - Moisture indicator
Located on the EXV, permits control of the unit charge and
indicates moisture in the circuit. The presence of bubbles in
the sight-glass indicates an insufficient charge or non-con-
densables in the system. The presence of moisture changes
the colour of the indicator paper in the sight-glass.
10.8 - filter drier
The role of the filter drier is to keep the circuit clean and
moisture-free. The moisture indicator shows, when it is
necessary to change the element. A difference in tempera-
ture between the filter inlet and outlet shows that the
element is dirty.
10.9 - sensors
The units use thermistors to measure the temperature, and
pressure transducers to control and regulate system opera-
tion (see 30XA - Pro-Dialog Control IOM for a more
detailed explanation).
Summary of Contents for Aqua Force 30XA
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